DECEMBER 1977 • 75 CENTS • A HARCOURT BRACE JOVANOVICH PUBLICATION

ELECTRONIC TECHNICIAN/DEALER WORLD'S LARGEST TV-RADIO SERVICE & SALES CIRCULATION

Medical Electronics: Is there a place for you?

Modern chroma circuits, part II

ETD's 1977 Index

Admiral's newest chassis

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PTS SERVICENTER LOCATIONS

MIDWEST Herne Off ice

BLOOMINGTON, IN 474101 5233 S. Hwy. 37. P.O. 272

812.824-9331 CLEVELAND, OH 44134 5682 State Road 216-845.4460

KANSAS CITY. KS 66106 3119A Merriam Lane. P.O. 6149

913.831-1222 MINNEAPOLIS, MN 55408 815-W. Lake St.. P.O. 8458

612.624.2333 ST. LOUIS, MO 63130

8456 Page Blvd.. P.O. 24256 314.428-1299

DETROIT, MI 48235 13707 W. 8-Mile Rd. 313-862.1783

GRAND RAPIDS. MI 0501 1134 Walker Northwest

P.O. 1435 616-454-2754

CINCINNATI, OH 45216 8172 Vine St.. P.O. 15491

513-821-2298 MILWAUKEE, WI 532111 7211 Fond du Loc 414-464-0789

COLUMBUS. OM 43227 4005A E. Livingston 614437-3820

INDIANAPOLIS, IN 46202 28 E. 14th St 317-631-1551

DAVENPORT, IA 521105 2024 E. River Dr.. P.O. 187

319-323.3975 OMAHA. NE 68132 5008 Dodge Street 402-558-1800 CHICAGO

Berkeley. IL 60163 1756 S. Taft Street 312.449-2082

SOUTH ATLANTA, GA 30311

2180 Campbellton Road P.O. 42558 404-753D007

JACKSONVILLE. FL 32210 1918 Blanding Blvd.. P.O. 7923

904-389.9952

WASHINGTON. DC Silver Spring MD 20910 8880 Brook villa Rd 301-565-0025

CHARLOTTE. NC 28225 726 Seigle Ave.. P.O. 5512

704.332-8007 BIRMINGHAM, AL 35201 210 N. 9thSt PO 1801

205-323 2657 MEMPHIS, IN 35118

3614 Lamar Ave.. P.O. 18053 901-365.1918

NORFOLK. VA 23504 3118 E. Princess Anne Rd.

804.625-2030 NEW ORLEANS

Metairie. LA 70004 3920A Airline Hwy.. P.O. 303

504.837-7569 TAMPA, ft 33690

2703 S. Macdill. P.O. 14301 813-839-5521

NASHVILLE, TN 37214 2426 A Lebanon Rd. 615-885-0688

NORTHEAST SPRINGFIELD. MA 01103 191 Chestnut. P.O. 3189

413-734-2737 PHILADELPHIA

Upper Darby. PA 19082 1742-44 State Rd., P.O. 207

215-352-6609 PITTSBURGH, PA 15202

257 Riverview Ave. W. P.O. 4130 412.761-7648

E. PATERSON, NJ 07407 158 Market St.. P.O. 421

201-791-6380 BUFFALO, NY 14212

993 Sycamore St.. P.O. 1241 716-891-4935 BOSTON

Arlington. MA 02174 1167 Massachusetts Ave., P.O. 371

617.648-7110 SYRACUSE, NY 13204

418 Solar St.. P.O. 207, Salina Sta. 315-475-2330

BALTIMORE. MO 2121$ 5505 Reisterstown Rd.

301-358.1186

PACIFIC

SACRAMENTO. CA 95841 4351 D Auburn Blvd., P.O. 41354

916.482-6220

SAN DIEGO. CA 9210$ 5111 University Ave.. P.O. 5794

714-280.7070 LOS ANGELES, CA 90023 4184 Pacific Way 213.266-3728

PORTLAND. OR 17213 5220 N.E. Sandy Blvd

P.0 13096 503-282.9636

SEATTLE. WA 98109 432 Yale Ave. N. P.O. 9225

206-623.2320

M OUNTAIN

DENVER Arvada, CO 80001

49511 Allison St, P.O. 672 303-423.7080

SALT LAKE CITY, UT 84106 1233 Wilmington Ave

P.O. 6218 801.484.1451

PHOENIX. AZ 85009 2916 West McDowell Rd

602-276-1218

SOUTH WEST

LONGVIEW, TX 75601 110 Mopac Rd P.O. 7332

214-753-4334 OKLAHOMA CITY. OK 73106 3007 N. May, P O. 60566

405-947-2013

HOUSTON, TX 77207 4326 Telephone Rd.. P.O. 26616

713.644-6793

NE WS OF THE INDUSTRY

Sylvania-Panasonic Join Home Video Tape Parade Panasonic and GTE Sylvania are the latest to join the growing list of U.S. television manufacturers who will market home video cassette recorder/ players in time for Christmas this year. Both have opted for Matsushita's two and four hour recording format, the same unit being marketed by RCA which caused industry waves by pric-ing their unit at a suggested retail of $1,000 earlier this year. Matsushita, of course, is Panason-

ic's parent company. Panasonic's entry into the field

began about two weeks ago with their unit, called Omnivision IV, going for a suggested retail of $1,095. Sylvania, on the other hand, delayed putting their units on the market until an ini-tial round of distributor service semi-nars could be conducted around the country. At press time, no decision had been reached by Sylvania on price or what they will call their version of Matsushita's machine. Following the industry trend, both

will offer optional black and white television cameras for a price in the neighborhood of $300. Still taking a wait and see attitude

regarding VCR units are General Electric and Admiral among the major U.S. manufacturers. Sony, the first to market VCR in this

country with its Betamax two-hour maximum recording time, is also offer-ing its $1,300 unit through other manufacturers. Zenith Radio Corp., is thus far the only U.S. manufacturer having opted for this format, although it is also being offered through Toshiba and Hiatachi. Among the manufacturers selecting

Matsushita's VHS (Video Home Sys-tem) format are J VC, RCA, Mag-navox, Panasonic, and Sylvania. JVC is actually manufacturing the Mat-sushita designed unit. Quasar Electronics is the only man-

ufacturer offering a third variation of the VCR, a single head recording "Alpha Wrap" format with one or two hour record/play options. This unit, as of press time, was priced at $995.

Radio-TV Dealer Sales Boom

Booming color television sales, judg-ing by third quarter statistics, con-tinue to point to 1977 as a banner year, according to EIA figures. Color TV sales to dealers for Sep-

tember were 1,104,941, up 28.3 per cent from a year earlier and for the

nine-months totaled 6,208,922, up 20.5 percent over a year earlier. Total television also showed strong gains with the nine-months figure totaling 9,960,807 which amounts to an in-crease of 15.1 per cent over the nine months figures a year earlier. Both RCA and Zenith report color

TV sales to dealers at record or near record levels while other manufactur-ers report performances substantially ahead of last year. EIA also reported soaring dealer

sales in radio. For September 7,765, 263 units were sold, up 60.5 per cent over September of 1976. For the nine months, EIA said, total radio sales were 39,446,360 and this amounted to a hefty 35.6 per cent increase over fig-ures for the comparable period a year earlier.

Tube Warranty Practices Criticized

The Chicago chapter of NATESA (Na-tional Association of Television and Electronic Servicers of America) says members are becoming increasingly concerned over the "growing practice" of circuit tube sales without warranty and it is considering notifying the Consumer Advocates office in Wash-ington, D.C. According to NATESA president

George Weiss, "Ultimately it will be the consumer who will get burned if this trend continues." Although manufacturers about two

years ago discontinued warranties on circuit tubes, distributors were giving a 5 per cent discount to cover faulty tubes. Now, Weiss said, some dis-tributors in the Chicago area have dis-continued the practice of passing on the 5 per cent discount to service deal-ers and others are contemplating fol-lowing suit. "Right now I find in my own shop a

10 per cent tube failure rate, and it is not the $3 tubes that are giving out. It's the bigger $12 tubes. "If one of these breaks down in the

home there's the additional considera-tion of a $25 service call we have to sacrifice, so it's a problem of labor costs as well," he said. A statement released by NATESA

said that an August 12 letter to tube manufacturers and marketers calling attention to the situation has gone un-answered. The non-warranty policy "is conducive to a serious drop in qual-ity," NATESA charged, and added "it appears that such is already the case" since field reports indicate the 5 per cent allowance "definitely is not com-pensating for the cost of needed re-placement and certainly not for the cost of calls." In addition to the proposal that the

Consumer Advocate be notified, NATESA said it was also suggested that servicers "find new sources re-

DECEMBER 1977, ELECTRONIC TECHNICIAN/DEALER / 1 F'TS ELE CTR ONI CS, IN C. . for more details circle 102 on Reader Service Card

RIC IARD W. LAY Ed :3r 43 East Ohio Street Chi:ago, III. 60611 (3-'2) 467-0670

DC4 W. MASON ME -aging Editor 1 East First Street Duluth, Minn. 55802 (2-8) 727-8511

AIRED A. MENEGUS Publisher 757 Third Avenue Nei.% York, N.Y. 10017 (2- 2) 888-4382

DA'rlD J. HAGELIN s3ociate Publisher 3nc General Manager

TOY GRENEY Put:. ishing Director

JOHN PASZAK :raphic Design

CEBBIE PORKKONEN Production Manager

_IE PEARSON Jlation Fulfill mnt

GENE BAILEY Manager, Reader S?svices

DAWN ANDERSON Classified Ad Manager

ADVERTISING OFFICES

DA D J. HAGELIN 43 East Ohio Street Ch Gag°, III. 60611 :31::.) 467-0670

CHUCK CUMMINGS Ad *pace South/West 613 North O'Connor irvIng, Texas 75061 (214) 253-8678

ROBERT UPTON Tiky0, Japan C.P.O., Box 1717

ELECTRONIC TECHNICIAN/DEALER

DECEMBER 1977 • VOLUME 99 NUMBER 12

THE COVER: Raymond Lipinski, Acting Director of Biomedical Engineering at Northwestern Memorial Hospital. Chicago, adjusts a non-fade display monitor in the hospital's Intermediate Coronary Care Unit. Telemetry signals transmitted from mobile heart patients allow the staff to monitor heart functions in real and delayed time.

18 A look at biomedical electronics servicing What you need to know to break into this expanding field and what you can expect when you gel there By Joseph J. Can, CET

24 Admiral color television for 1978 A new chassis—the 25M55M—is introduced and designed to handle Admiral's new 90 degree delta CRT. We take a look at the new circuits.

27 Servicing modular chroma—Part two The conclusion of our two part series on servicing modern color circuits emphasizes proper signal tracing methods. By Bernard B. Daien

30 The ET/D Annual subject reference index An alphabetized subject-to-issue listing of editorial topics and servicing tips published in ET/D during 1977.

DEPARTMENTS

1 NEWS OF THE INDUSTRY

8 NEWSLINE

12 TECHNICAL LITERATURE

11 FROM THE EDITOR'S DESK

14 SERVICE SEMINAR

34 TEST INSTRUMENT REPORT

36 DEALER'S SHOWCASE

39 NEW PRODUCTS

46 CLASSIFIED ADS

48 ADVERTISING INDEX

49 READERS SERVICE

51 TEKFAX

A HARCOURT BRACE JOVANOVICH PUBLICATION 'ABP

HARCOURT BRACE JOVANOVICH PUBLICATIONS Robert L Edell. Chairman. Richard Moeller, President Treasurer, Lars Fladmark, Senior Vice President, Thomas Greney, Vice President, Ezra Pincus. Vice President. James Gherna. Vice President Lois Sanders. Vice President. Harry Ramaley, Vice President, Joe Bilderbach, Vice President, George Glenn Editorial Director

ELECTRONIC TECHNICIAN DEALER is published monthly by Harcourt Brace Jovanovich Publications Corporate offices. 757 Third Avenue. New York, New York 10017 Advertising and editorial offices 43 East Ohio Street. Chicago, Illinois 60611 and 757 Third Avenue, New York. New York 10017 Editorial, Accounting, Advertising Production and circulation offices 1 East First Street, Duluth, Minnesota 55802 Subscription rate one year. 58 two years, $14 three years, $18 in the United States and Canada Other countries one year. 515 two years, $24 three years. $30 Single copies 75 c in the U S and Canada all other countnes $2 Second Class postage paid at Duluth. Minnesota 55806 and at additional mailing offices copyright c 1977 Sy Harcourt Brace Jovanovich. Inc All rights reserved No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording. or any information storage and retrieval system, without permission in writng from the publisher

POSTMASTER Send Form 3579 to ELECTRONIC TECHNICIAN DEALER, P 0 Box 6016. Duluth, Minnesota 55806

2 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

Why fiddle with

cross-references... when replacing standard Japanese original equipment semiconductors? Buy the original Japanese number from HEP, such as 2SA495, 2SB468, etc.

Our broad line includes the Discretes, ICs and Modules most in demand by the professional service technician.

Time is money—HEP can save you both. And that's the name of that tune!

MOTOROLA

HER SEMICONDUCTORS

Write: Motorola HEP 705 W. 22nd Street Tempe, AZ 85282

Your complete semiconductor supplier. for more details circle 120 on Reader Service Card

DECEMBER 1977, ELECTRONIC TECHNICIAN/DEALER / 3

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1. ZENITH'S INSTANT PARTS PROGRAM

It's the easiest, least expen-sive Zenith inventory control system ever devised for TV service technicians.

Organizes the most needed, most used TV replacement parts so they're where you want them, when you want them.

And ZIP keeps these parts organized thru periodic checks by your Zenith distributor salesman who personally replaces slow-moving stock numbers with new, popular parts.

As a result, your original investment is protected and your supply of Zenith parts is always curren:

Call your Zenith distribu-tor now for all the details on the ZIP program that fits your needs.

yourshop so you service more sets... up more profits! 2. FINGERTIP CONTROL OF YOUR CURRENT TECHNICAL AND CROSS-REFERENCE MATERIAL

Now's the time and here's the way to end forever the costly nuisance of searching for current technical data, trying to find cross-reference material, and looking for the oldest and newest schematics.

With Zenith's new CRSP* Manual Organizer, you keep everything neat, clean, orderly.., right at your fingertips.

Housed in a beautiful, durable "organizer" is a 3-ring binder with 41/2 inches of catalog capacity...a "want" book... space for your most often used phone numbers... separate wells for note paper and pencils.., and even a chain-attached towel to reduce catalog-page soilage.

It's just what the doctor ordered for your se-vice shop. Comes completely assembled, ready to use.

Call your Zenith distributor now and find ou-. how you can put the Zenith CRSP Manual Organizer to work for you!

*Cross-Reference Sales Program

For your own reputation and in your customers best interest, always specify Zenith exact replacement parts and accessories.

7The04g1.121t quality goes in before the name goes onl)

Zenith Radio Corporation / Service, Parts & Accessories Division / 11000 Seymour Avenue / Franklin Park, Illinois 60131

for more details circle 131 on Reader Service Card

gardless of point of origin" or simply tell the customer there is no warranty even though "this obviously will...nul-lify guarantee on the set as well." In a letter sent to tube manufactur-

ers, NATESA said the present situa-tion "is not conducive to good industry or consumer relations (and) servicers being on the 'firing line' are catching most of the flak."

Zenith Seeks Supreme Court Decision; Announces Third Quarter Loss

Zenith Radio Corp., which announced in October a 25 per cent reduction in its U.S. workforce over the next year

and transfer of its module and chassis assembly operations to foreign shores, has officially asked the U.S. Supreme Court to review a lower court's ban on counter duties on Japanese consumer electronics products. Zenith has long been seeking U.S.

government intervention in what it has termed unfair competition. Specif-ically, Zenith cites the Japanese gov-ernment's practice of rebating to Japanese manufacturers excise taxes on consumer electronics products for import to the United States. Although Zenith won an initial U.S.

Customs Court ruling defining the re-bate as a Japanese government sub-

NEW FROM LEADER

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6 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

sidy to manufacturers, a federal ap-peals court reversed that ruling. Opposing the Zenith position is the

U.S. Treasury Department which fears a world trade debacle since many Japanese and European manufactur-ers are the beneficiaries of similar tax considerations by their governments on items for export in world trade. Ap-parently the U.S. is in a bind over the situation since the sanctioned General Agreement on Tariffs and Trade has said such counter duties would violate world trade agreements. Joining Zenith in its bid to have the

Supreme Court settle the issue are several U.S. television manufacturers and labor groups as well as the U.S. Steel Corp. Zenith contends the effect of the

Japanese government's rebate policy allows consumer electronics products sold in Japan to be sold in the United States for up to 40 per cent less in price. If the Supreme Court decides to hear

the issue, it will most likely hand down a decision sometime around the first of the year. In another announcement Zenith

said it had suffered a $12.9 million third quarter loss, primarily through the write-off of an inactive color pic-ture tube plant in Lansdale, Pa. The loss amounted to 69 cents per share with the plant write off accounting for 65 cents. For the first nine months Zenith

sales totaled $724 million, compared to $699 million in 1976 and net income totaled $600,000, compared to $24.8 million for the comparable period a year earlier.

CB Or Not CB

CB radios are often the whipping boy for all kinds of reported television in-terference, reports the Citizens Radio Section of the Electronics Industries Association, when in fact the problem may be common household appliances. That statement came from the Citi-

zens Radio Section as it proposed new technical standards to eliminate what it called the "occasional interference" which unwanted signals from CBs cause in TV sets. The section said in a proposal to the FCC that CB harmonic emissions be limited to 75 decibels below the station's 4 watt power limit. "Harmonics have no communica-

tion value to the CB user, but may have the potential for interfering with certain 'IT channels," especially in high density residential areas. How-ever, the CB section said, a study of American households reveals that the typical private home might contain 60 to 100 devices capable of TV and radio interference, devices such as auto ig-nitions, household appliances, fluo-rescent lights, electrical toys "and

many other sources." In addition, "no significant decrease

in reported cases of CB interference to TV reception can be expected until firm action is taken to end the use of illegal power amplifiers."

GTE Reports Earnings Increase

General Telephone and Electronics Corporation reports third quarter earnings of $143.4 million, an increase of 26 per cent over third quarter re-stilts a year earlier. According to a company spokesman

the improvement was attributable to "substantial increases" in manufac-turing earnings from the communica-tions products and consumer elec-tronics products groups. Theodore F. Brophy, chairman, said

the consumer electronics products group sustained a $4.3 million third quarter loss in 1976 but this year showed a $444,000 gain.

Briefs EIA's 10-year forecast for the gov-

ernment electronics market indicates a modest real growth rate of 1.4 per cent, or 7.4 per cent when the expected 6 per cent rate of inflation is counted in—EIA's Board ofDirectors has voted to support Sony's position in the lat-ter's legal battle with Universal Studios and Walt Disney Studios. Universal and Disney allege copyright infringement through the marketing of Sony's videotape recorder equip-ment—and, Donald R. Kronenwetter has been named vice president of GTE Sylvania's newly reorganized Distrib-utor and Special Markets Division. It was formerly known as the Replace-ment Markets Operation. •

Help. Our Cities. Our Oceans. Our Trees. Our Rivers. Our Air. Our Mountains. Our Fishes.

Our Deserts. Our Tomorrows.

Give a hoot! Don't pollute.

Seeking Original Japanese Replacement Parts for CB and Stereo Repair Use?

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Original Japanese Transistors FET, IC, Diodes CHECK OUR LOW PRICES!

TRANSISTORS 254 818 I 40 2SC 403 59 25C 1449 I 00 250 357D I CO 59 25A 839 2 '5 2SC 430 2 65 2SC 1451 1 60 2SD 358 I 30

5r90 222sc5c5C 898,98721 25A 49

I 10 251 841 59 25C 454 • 40 25C '475 1 40 2SD 360 I 20 59 2SC 458 59 25C 1478S 70 250 371S 280

251 70 59 2SC 900

fig ;55 9113 i 10

59 25A 847 59 25A 850 59 25C 1509 1 10 25D 382

340 2255A8 10821 70 25C 460 59 25C 9?)

50 2SC 945 59 2SC 158. 8 50 250 388 8 50 2SA 234 59 2SA 8721 254 342 9020 22555A 90: I i 0058 2SC 4846 1

59 25C 182 60 2SC 959 1 20 2SC '586 6 60 250 *24 i 30 2S0 427 1 10 2513 525 2 80

154 353 2 OD 256 55 I 60

I ri 225C ;6622: I 10 2SC 485 59 25C 486 60 25C 971 i 10

2SA 377 90 256 75 00 25C 983 I 03 25C '628 1 30 2SD 526

1 C900 22Z 2 1646697

25A 440 254 483 60 2SC 984 59 25D 555A 6 60

90 3 CO 2S6 77

1 60 250 610 25A 484 25* 485 2 50 258 186 59 2SC 495 90 2SC 1000131 55 2SC 1674 95 2SC 1014 I 20 2SC 1675 59 FET 25/ 489 1 00 258 187

1 60 258 202 59 25C 497 59 2SC 509 60 1 60 25C 517

70 2SC 1017 I 40 25C 1678 2 5925 22SSICK 3018 90 25A 495 70 2513 220 1 10 2561 303 70 2SC 535 59 25C 1018 I 20 2SC 1682

59 25C 1030C 2 80 2SC 16,91 10 2S4 .96

70 2SC 1708 z :45 222i66K 40,433 10 59 25C 536

70 25C 1047 70 2SA 497 254 509 1 60 256 324

70 2513 337 30

25A 525 2 50 256 367 I 6070 22scSC 553387A I so 2SC 562 2 15 25C 1060 2 25 25C 1728 200 2SK 49

1 10 2SC 1061 1 40 2SC 1730 30 I Z 22552 11060 4 40 2SC 1760

2SA 537 2 25 2SB 3686 2 1105 226c5C 656320 70 256 379 2 ro 22:6K 153 30

55 254 539 251 561 59 250 400 I CO 22scSC 11877165 4 2545 33S5KK 3252 59 256 405 59 25C 627 340 25 2SA 562

25 70 25C 6324

70 356 39 254 5641 254 565 1 5610 2255 68 448157 75(;)70 222: :I 11111165i 43 4040 22scsc ro: 25 40 2SC 614

50 254 566 3 40 258 434 70 2SC 645 20 25C 650 25C 1909 4 5409 33: 6K 44°1 50

251 606 1 90 256 463 1 5309 22, cSC 11112164 A 4, 9030 25C 1951 1 10 3SK 45

1 10 2SB 471 6050 2SC 680668 260 2SC 1162 1 10 2SC 1957 1 20 6414 10 1 40 2SC 1166 00

2255: 66224, 3 60 256 472 80 2SC 68/ IC

40 2SA 628 59 2SC 1969 4 90

20 2SC 6938 70 CO 2SC 696 2SA 634 905 225568 449724 59 2SC 1173

60 25C 7084 1 90 2SC 1177 14 00 25C 2028 L0 rC 11,8377 4"480 AN 231,45° . 2SA 610 59 256 507 70 2SB 509 I 95 2SC 1175

70 254 643 54 22552 12188110 1 172,,i 222i 22R9292, 33 WI° 98BAAA 551211 5:1 70 254 659 59 2SB 514 490 256 526C 90 2SC 710

41 00 70 59 2SC 1213 ?SA 663 59 2SC 1222 00

90 25C 711

254 666 70 256 527 70 2513 5280 30 2SC 712 19 2SA 672

2SA 673 70 258 531 70 2SE1 536 90 2SC 717 60 2SC 730 4 40 25C 1226 1 CO45 2255CD 2821728 233 8013 SAAN 76474005M

59 25C 1237 4 25 2SD 75 60 1 6010 STAN 77055480 P 300

3 40 2SC 732 I 60 25C 733 59 25C 1239 3 50 2S0 90

70 2SD 91 254 678

70 258 537 70 2SB 539 I 60 25C 73• 59 2SC 1279 1 60 251 683 25A 684 490 2SC 735 59 25C 1306 • 40 2SD 92

70 2S8 541 4 40 2SC 738 59 25C 1307 4 9059 22550D ;3018 3100:3' TA 1062 II 9090

2SA 695 I 20 TA 7205P 3 90 70 258 55. 10 00 2SC 756 2 00 TA 7310P 3 9S

2SA 697 2SA 706 1 60 2S8 557 3 40 25C 763 70 2SC 773 2 8059 225c5C 113311320 .59 2SD 142

1 40 2513 5618 70 256 564

2SA 715 254 719

70 256 595 90 2SC 774 1 90 2SC 775 70 2SC 1317

1 60 2SC 1318 59 250 143 2 BO *PC 59292 81 6060 21 5040 PLL 02A

DIODES 208 720 70 2513 6004 7 00 2SC 776 2I 6595 22 S CS C 1313207 1 5z 4 }55 :9 222221 0(1)30D ;05i:75887 8 I 00 59 2SC 183

3t 408659 I: SS5 84331882 45

225SAA 272521

59 2SC 184 59 25C 777 45 59 2SC 778 350 2SC 1342

4 10 IS 953 2SA 726

45 59 2SC 28' 59 2SC 781 360 2SC 1344

45 251 733 2 65 25C 284 265 2SC 13450 59 ?so 217

I 40 2sC 783R 3 60 2SC 1359 I 40 2SD 218 59 25C 1360 1 CO 2SD 223 3 70 15 100725A 740 2255: 3 70 /SC 367 90 25C 784 70 25C 785 1 90 IS 1209 45

774445P 440 25C 369 45 580 2SC 371 59 25C 789 2SC 1364 1 40" 221C D '2264

, 0070 2SC 1362 1 90 15 1211 1 60 IS 1555 32

225SAA 775047 59 25C 793 2 BO 2SC 1377 4 5990 225500 223427 32 59 25C 799

59 ?SC 372 25A 756 3 40 25C 373 59 IS 1588 45 2SA 758 5 80 2SC 374 59 25C 815 59 2SC 828 3 60 25C '383 59 25C 1400 59 250 235 59 2SC 1402 3 70 2SD 287 1 CO IS 1885 I 00 IS 2076 45

45 59 2SC 383 I 10 25C 381 59 25C 829 59 2SC 1403 370 2SD 313 3 70 15 2093 45 70 2SC 382 59 25C 838 59 25C 1419 1 10 2SO 315 1 10 IS 2473 1 20 IN 34 25

2SA 174

22:84 779877 2SA 814 1 90 2SC 387 59 25C 839 59 2SC 1444 2 BO 2SD 325 I to IN 60 25 2SA 816 70 2SC 391 59 2SC 870 59 2SC t 448 1 10 250 3560 1 10

PRICES MAY CHANGE WITHOUT NOTICE COD ORDERS WELCOMED Less than $500 no deposit required

IMMEDIAlE DELIVERY WITHIN 48 HOURS ON ALL TRANSISTORS IN STOCK Minimum order $10 00 Ohio residents add 4% sales tax Add $1 00 postage and handling Ouantity discount prices Ask For Our Complete Price List Maunlacturer inquiries Welcomed

ALL PARTS GUARANTEED AGAINST FACTORY DEFECT

TOLL FREE TELEPHONE: Nationwide 800/543-1607 LOCAL 513/874-0220

Ohio 800/582-1630 874-0223

Hours Mon.-Fri 10-7: Sat. 11-5

FUJI-SVEA ENTERPRISE a Division of Fuji-Svea Incorporated

Dept. ET P.O. Box 40325 Cincinnati, Ohio 45240

...tor more details circle 114 on Reader Service Card

DECEMBER 1977, ELECTRONIC TECHNICIAN/DEALER / 7

NE WSLINE

EXTENSION OF 23-CHANNEL CB SALES IS DENIED. The FCC has turned down requests from 23 CB manufacturers, importers, distributors and retailers for an extension to Aug. 1, 1978 of the deadline for sales of 23-channel transceivers. Thus, the deadline stands at Jan. 1 at which time all 23-channel radios must be off the re-tailers shelves. The FCC felt that an extension would be unfair to those who have already lost money unloading their 23-channel inven-tories.

MEANWHILE -- CB MANUFACTURERS ARE HAVING MONEY PROBLEMS. The E. F. Johnson Co., Electronic News reports, is negotiating with its banks for a restructure of its credit agreement in accordance with the company's changed financial situation. Because of an announced third quarter loss of $4.4 million, the firm expects to grant the banks security interest in the balance of its assets. Johnson spokesmen say year-to-date sales were hurt by cost of liquidation of 23-channel radios and oversupply of foreign imports.

DYNASCAN REPORTS LOSS FROM CB SQUEEZE. Dynascan, producer of Cobra CB products, has reported a loss of $682,000 or 24 cents a share on sales of $12,432,000 in three months ended Sept. 30. Dynascan's president, Carl Korn, "Excess supplies of 23-channel and 40-channel models have led to a continuation of price-cutting, and to reduced sales of 40-channel models." Korn said, however, the firm's Indus-trial Products group continued to show strength with sales exceed-ing last year's record in test equipment and radio remote controls.

SHARP SURVEY REVEALS LIKELY SALES POINTS FOR HOME VTR. A survey by Sharp Electronics reveals that the TV departments of mass merchan-disers and department stores, along with appliance stores and hi fi specialty shops are the most likely places through which home VTR will be sold. Most department stores and mass merchandisers (92%) said the addition of home VTR offered a new opportunity to form "a more advanced consumer entertainment department."

COMPETITION UP -- PRICES DOWN IN VTR. Following the lead of others, Sony has dropped the list price for their Betamax from $1,300 to $1,095. This is still $100 above the new price announced by Zenith for the same unit. Zenith's new price is $995, which makes it com-petitive with the RCA offering.

FOUNDER OF THE TRIPLETT CORPORATION DIES. One of the few remaining pioneers of the electronic industry, Ray L. Triplett, 93, founder of the Triplett Corporation, died in Florida on October 25. His one room factory, founded in Bluffton, Ohio in 1904, has grown into one of the major test instrument manufacturers.

EICO MOVES TO NEW LONG ISLAND LOCATION. The EICO Electronic In-struments Company, producer of electronic kits and wired equipment, has moved from Brooklyn to new quarters at 108 New South Road, Hicksville, NY. The new location will permit intergration of the company's engineering, production and shipping departments into one modern building.

WINTER CES SHOW IS A SELL-OUT. The 1978 Winter Consumer Electron-ics Show, to be staged for the first time in Las Vegas, Jan. 5-8, is a complete sell-out with over 75 applicants on the waiting list.

8 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

• I

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0' 114

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• 8#$ E V

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Charles Varble, Jr., Chart Television, St. Ann, MC) 63074

"I dotit the quality of my service...

or the quality of the parts I use.

A.1. •

.410:114 '

OM.

• Ott 41

Your reputation is our reputation Tube Products Department • Owensboro, Kentuckv 42301

GENERAL Es) ELECTRIC

From blisters to boxes to bags.

Mallory's got the winning team for your solderless terminal needs.

Mallory solderless terminals are available now — packaged to suit your needs. These

crimp-type terminals and connectors fit virtually all popular applications and ccme in a complete range of sizes from 26 through 4/0 AWG.

Buy the winning team for convenience and reliability. See your Mallory Distributor. Or

contact Mallory Distributor Products Com-pany, a division of P. R. Mallory & Cc.. Inc., Box 1284, Indianapolis, Indiana 46206. (317) 856-3731.

MALLORY Capacitors • Controls • Fastening Devices • Resistors • Security Products • Serruconductors • Solderless Terminals • SonalErt Signals • Switches

...for more details circle 118 on Reader Service Card

FROM THE EDITOR'S DESK

VTR repair: yes or no? A recent phone check with many of the television manufacturers who are bringing out one of the two basic VTR units in titre for Christmas (see Industry News Page) reveals that training sessions are in full swing. If your service shop is contemplating getting into this service area as it develops, now would appear to be the time to make that decision. However, there are several things you should keep in mind. Primarily, the considerable

investment in equipment you will have to make to service these very complicated machines will have to be weighed against the limited amount of service that will be available initially. VTR service at present is not self-supporting. Whether it becomes self-supporting in the future is a judgmental decision that can be argued either way. However, for the present, it seems likely that to make your investment as economical as possible you'll have to know both the Sony Betamax and the Matsushita VHS formats. In addition to freeing up a technician for the four or five days of schooling on VTR

units, you'll need the following in the way of basic test equipment (in addition to the special jigs which each manufacturer ;s selling for servicing the servo-mechanical parts of these units). —An NTSC color generator —A dual trace, delayed sweep scope with channel 2 polarity inversion and TV sync

separator capabilities. —A quality frequency counter with at least 7 digit readout and 4 place period display. —And, a quality digital VOM. Most of the manufacturers have just finished first level training sessions for their

distributors. Now it is up to the distributors to continue with the training cycles, sometimes with support from the manufacturer, in other cases without. To be blunt about it, the distributor level training will be geared toward locating authorized retail dealers with service centers and "serious" independent shops willing to purchase the specialized test equipment that goes with the specific VTR unit. To assess your chances of getting into this area, it would be best to contact your local distributor. Meanwhile, here's a rundown on who's doing what in the service training area on VTRs. SONY: Began Sept. 25th in its four U.S. regions 5-day training seminars aimed at

Sony Service Centers, servicing dealers, and selected independents. GTE SYLVANIA: Began Oct. 17th special 4-day distributor training seminars at various

U.S. locations. Second round of training to continue at distributor level with manufacturer support. ZENITH: Began 5-day session in mid-August for distributors, service centers and

independent dealers. Currently acceptirg class loads of about 30 technicians in Chicago. RCA: Started 5-day sessions for 70 cistributors in late August. Some distributors

began a special 1-day introductory course open to all service dealers and centers, plus a second level 5-day program for authorized service centers. MAGNAVOX: Began Nov. 14th, 5-day sessions for selected franchised independent

service dealers. Suffice it to say VTRs are complicated and precise electronic and mechanical

products. For instance, Matsushita's VHS unit contains 9 circuit boards which serve as 13 when operated in the 2 and 4 hour modes. Video information recorded on tape is an FM square wave, the chroma signal recorded on tape is beat down to 629 KHz, drive motors are clocked by video signals. In short, it's a whole new world. With this issue ET/D is beginning the -irst of a series of articles on VTRs, or VCRs, if

your prefer. I hope they will give you a better insight on what to expect when you come face-to-face with them in the field.

DECEMBER 1977, ELECTRONIC TECHNICIAN/DEALER / 11

OPTIMA VALUE SALE G. E., SYLVANIA. ZENITH, RCA, ETC.

75% Off LIST NEW JOBBER-BOXED TUBES 3A3 5 for $7.44 6JE13 for 15.50 50H8 5 for $8.75 „ 6J813 for 13.75

E 6BK4 5 for 13.81 C 61.843 for 14.94 .16FQ7 5 for $5.63 0 SIFQ7 for $5.63 60H8 5 for $5.88 C 120N7 for 10.38 613.17 5 for $6.69 C 17JZS for $7.69 60 W4 5 for $6.94 0 23Z9 for $9.44

11 6HA5 5 for $7.13 ji 38H E7 for 13.63 • All Tubes Not Advertised, Write In at 75 % off list. Sleeves Only. Singles at 72 % off list.

Special: 100 60118's G.E. $99.00.

TRANSISTORS EQUIVALENT UP TO 90% OFF LIST .35 each -Minimum 20 per number

SK [CO 6K [CO CI 3018 108 0 3114 159 E 3024 128 0 3122 123A C 3025 129 0 3124 123A

SK O 3027 ▪ 3064 o 3103 O 3041 o 3079 o 3115 3248

Minimum 6 of a Number [CO 130 184 157 152 162 166 186A

ea. 900 ea. 704 ea. 604 ea. 704

ea. 11.50 Ca. ea. 2.76

- 1165 3197 1058

235 ea. 12.50 Ca. ea. 2.50

RCA ORIGINAL TRANSISTORS 0 8K 3040 ea. $2.90 0 3501 ea. $3.45 0 8K 3115 ea. $6.75 E 3504 ea. $5.00

JAPANESE TRANSISTORS 0 260 1678 $2.00 E TA 7205P $2.50 0 2130 1306 $2.00 C TA 7204P $2.50 0 280 2098 $3.00 0 UPC 1025H $3.25 2130 517 $2.50 Li AN 214 $2.50

IC'S EQUIVALENT TO ECG $1.00 each Minimum 5 of a Number

0 706 0 709 0 710 3 712 0713 0 714 0718 0 719 0 722 LJ 723 0 726 0 731 0 740 0 743 0 748 E 780 0783 0 788 0790 0791 E 799 0 912 0 9230

YOKES E Y88 0 Y130 E, Y94 0 Y105 0 Y119 095.2779 ea. $5.75

E Y153 0 DY92C 0 DY99AC ea. $8.95

DIODES, RECTIFIERS. EQUIVALENT 213500 PIV Color Focus Rect. 10 for $4.95 C 2.5a 1000 PIV IR 170 100 for $9.00

Boost Rect. 20 for $6.00 ES71.-Zen. Triple, 212-139 ea. $6.50 E Admiral Triple, ea. $4.95

AUDIO- CARTRIDGES- NEEDLES EQUIV.

E Astatic 133 ea. $1.95 C 142 ea. $1.45 j USSR 8C7M2 0 SC8H2 0 SC12H ea $1.90 EV 26 ea. $1.50 0 EV 5015 ea. $2.15 ▪ GE LC2 ea. 8.815 0 OECC650 0600 ea. $2.95 Panasonic EPO 42 ea. $2.00

O EPC7OLTS ea. $1.00 C Tetrad All Numbers 8N-1 to 6 ea. $1.95 O Varco CN75 0 YN4B ea. $1.40 ▪ ST4X ea. $1.15 E Zenith 142-166 0 167 0168 ea. $2.75 C N44 077 0 75 091 1/15 ea. $2.25 9111/ 8T170 10 for $6.90

CB HARDWARE and WIRE PL 259 10 for $3.10 0 PL 258 10 for $3.90 3 ft. 116513 2PL259 10 for $9.90 20 ft. S2 00

E 20 ft. R058 1PL259-1 Spade Lug $1.70 C CB Lightning Arrestor 994 050 ft. 59U incl. F. conn. ea. 1.89 100 ft. 3.69

1350 ft. RO SU ea. $7.55 C 100 ft. $12.95 O400 ft. 300 ohm wire 40' hanks white $5.00

GENERAL 430 Min. Irish Cassette Tapes 24 for $8.00 $300 Surprise Package $10.00

0100 Asst. Caps $4.00 R Asst. Belts $

47..000

0 0300 ohm signal splitters. (TV) 10 for $7.90 0 TV Lightning Arrestors 10 for $5.00 0 75-300 ohm Matching Trans. 10 for $5.90 0 Deluxe Lock Mounts w P1259 $3.95 0 Speco 2 station Intercom $7.96 19" & 25" Color Boosters 3 for $10.00 C Cell Batteries 24 for $2.40 Stereo "Y" Adaptors 'a" 10 for $6.90 9 Track Head Cleaner 10 for $5.90 Clothes Pins 100 for $10.00

SPEAKERS

84" 4 for $4.00 8" ea $2.95 315 4 for $5.00 0 4:6 . 4 for $6.00 04:10 ea. $3.95 E 5:7 speaker kit incl. grill ea. $1.95 C 6:9 kit incl. grill and SwIck Ca.

OP-69 -Min. 10 e. $ 9 Ca. 0 1 Pr. 20" Speaker Baffles. Incl.

Speakers $19.95 C 1 Pr. 12" Speaker Baffles, Incl.

Speakers $9.95

WANTED: Electronic Merchandise. WILL PAY CASH . . .

Letters of credit and all checks placed on de-posit with Manufacturers Hanover Trust Bank. N.Y.C. Master Charge, Min. $100, C.O.D.'s 50 % Dep. BankAmerIcard-VISA, Min. $100, CO D's 50 % dep. Mm. order $75 FOB Brook-lyn. N.Y. Catalogue $3, refundable upon order. SEND CHECK OR MONEY ORDER TO:

OPTIMA ELECTRONICS Box 372 Ryder Street Station

Brooklyn, New York 11234

Phone (212) 439-7434

TECHNICAL LITERATURE

Indicator Lights and Lampholders are catalogued colorfully and com-pletely in new literature available from Chicago Miniature Lamp Works. The new catalog, No. 7800, describes the company's full line of standard lenses, incandescent and neon indi-cators, cartridge hardware and lamp-holders. Each page covers a separate series, showing features, dimensional drawings, electrical and mechanical specifications. Also included are lamp types suggested for use in the various indicators. Available free from George Neeno, Chicago Miniature Lamp Works, 4433 N. Ravenswood Ave., Chicago, Illinois 60640.

Chemicals For Electronic Servic-ing are described and illustrated in the latest catalog from the Rawn Company. The new 12-page catalog covers such chemical servicing aids as tuner cleaners, tuner lubricants, cir-cuit and component coolers, cements for all types of repair work, protective and insulating coatings, solvents and polishes. Prices are included. This new catalog is available free from Rawn Company, Inc., Box 9, Spooner, Wis-consin 54801.

Getting To Know OSCAR-From the Ground Up is the title of new guide book to amateur communica-tions satellites from the American Radio Relay League. In 14 sections, the new book provides an introduction to space communications, the equip-ment needed, a description of the brand-new OSCAR satellite and fu-ture ones now under construction. Each copy of the book contains a four-color tracking device that makes find-ing the satellites an easy task. Avail-able for $3 from The American Radio Relay League, 225 Main Street, Newington, CT 06111.

CB Microphone Adapters for 1080 models and 153 CB transceiver brands are cross referenced and described in a new 4-page guide available from GTE Sylvania. The new guide identifies the right Sylvania Match-All adapter to use with the different CB brands and models. The guide, which is in al-phabetical order, also contains a list-ing of those CB radios which require other Sylvania microphones. Avail-able free from CB marketing Dept., GTE Sylvania Inc., 100 First Ave., Waltham, Mass. 02154.

Pre-packaged Electronic Compo-nents are shown in the latest catalog from Sprague Products. Catalog C-651

contains 28 pages of information on carded components ranging from all types of capacitors, including trinners, to carbon-film and vitreous-enamel resistors, silicon and germanium transistors, rectifiers, diodes, inte-grated circuits, quartz crystals, op-toelectronic devices, switches, wiring components, pulse transformers, and CB noise filters. Available free from distributors or from Technical Infor-mation Service, Sprague Products Co., Marshall Street, North Adams, Mass 01247.

Mobile Communications Antennas for all frequencies used for mobile-to-mobile and mobile-to-base opera-tions are described in the latest catalog from Larsen Electronics. Both quarter wave and gain types are fea-tured with a variety of permanent and temporary mounts included. Over 200 antenna types, frequency ranges, and mounting styles are detailed. The catalog is indexed by both number de-signations and description for easy finding of specific styles or models. Available free from Larsen Elec-tronics, P.O. Box 1686, Vancouver, WA., 98663.

Sub and Microminiature Switches for many applications are covered in the most recent catalog from C & K Components. The 48-page catalog de-scribes and illustrates brand-new of-ferings of the company in the first five pages ranging from actuators, bush-ings, terminations and interchange-able nylon lever handle caps for toggle switches. Also in the catalog are speci-fications for: toggle, rocker and lever handle, printed circuit mounting, snap-acting pushbutton, alternate and action and momentary pushbut-ton, subminiature and microminia-ture pushbutton, illuminated rocker, power, slide, and thumbwheel switches. Available free from C&K Components, Inc., 103 Morse St., Watertown, MA 02172.

The Proper Use & Care of Hand Tools is the subject of handy 88-page booklet available now from Klein Tools, Inc. Tools covered are pliers, screwdrivers, wrenches, striking and struck tools, vises, clamps, snips, tool boxes, chests and cabinets. The book-let contains hundreds of illustrations which show how to select the proper tool for various jobs, the care and maintenance of tools and many of the hazards which can result from misuse of tools. Cartoon characters are used to emphasize the test. This new litera-ture is available free from Klein Tools, Inc., 7200 McCormick Road, Chicago, Illinois 60645.

Quartz Crystals Technology is cov-ered in a new 150-page manual avail-

...for more details circle 124 on Reader Service Card 12 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

able from the Sentry Manufacturing Co. The new book is said to take the mystery out of understanding and using quartz crystals. It helps you specify what you need for your com-mercial two-way, marine, aircraft, public service, ham and monitor radios. Also, frequency charts for 23 channel sets and what crystals are need for conversion to 40-channels. Available for $2.95 from Sentry Manufacturing Co., Chickasha, Oklahoma 73018.

AC/DC Power Supplies and Con-verters are described in a new 8-page booklet from Analog Devices. Full product summaries are included of the firm's 900 series AC/DC modular power supplies, available with 5 to 24 volt output and current ratings from 25 inA to 2A and modular DC/DC con-verters that satisfy a wide variety of floating single 5V and dual 15V power requirements. The booklet also de-scribes the newest additions to the company's line of chassis mount supplies. Available free from Analog• Devices, Inc., P.O. Box 280, Norwood, MA 02062.

Test Instruments, Assembled and in Kit Form are covered fully in the 1978 catalog from Eico. The new 38-page book features their complete line of electronic kits and factory assem-bled instruments, burglar/fire alarm systems, and CB accessories. Com-pletely new test instruments for 1978 are: portable digital multimeters, function generator, portable IC color generator, digital frequency counters, a solid state triggered sweep 10 MHz oscilloscope, a self-service tube tester and a digital power supply. New CB accessories include a 100 watt in-line wattmeter, an SWR/Power meter, a mobile field strength meter and power supplies. Available free from Eico Electronic Instrument Co., Inc., 108 New South Road, Hicksville, N.Y. 11801.

New Test Instruments in 9 separate product categories and designed for use in industry, quality control, ser-vice, education and communications are featured in a newly published 12-page short form catalog from Leader Instruments. The new brochure fea-tures dual trace and single trace oscil-loscopes ranging from 30 MHz bandwidth down to 4MHz; digital multimeters with single pushbutton semi-automatic operation; audio analyzer systems; color bar genera-tors; counters, bridges and testers; signal generators for CB, audio and RF testing; wow and flutter meters; and 9 communications testers. Avail-able free from Patrick Redko, Leader Instruments Corp., 151 Dupont St., Plainview, N.Y. 11803. •

óu can be sure more times in more circuits in more places

than with any other multimeters on the market today

Each Sencore DVM is backed with 15 Megohm input im-pedance for one third less cir-

DVM38 $348 3'h DIGIT .1% DCV ACCURACY

AUTO-RANGING DVM A "prime" standard at your fingertips for measu:ements you can trust. Auto-ranging for extended low-level range and ease of operation. 15 Megohm input impedance assures .1% reading accuracy is maintained in solid state circuits. Highly sensitive, yet fully protected to 2000 VDC overloads. Hi. Lo Power Ohms circuit simplifies in-circuit

resistance measurements.

DVM37 T4°) $248 3% DIGIT .1% DCV ACCURACY

PORTABLE DVM Prime standard .1% accuracy on the bench or in the field for less than $250. The DVM37 is the most accurate portable DVM you can buy, with 15 Megohm input imped-ance for 50% more accuracy. Includes auto-matic features—Auto Zero, Polarity, Deci-mal, Overrange. Fully protected inside to over 2000V on all functions, including Ohms, and protected outside with super-rugged case. Full ranges for every test. Fingertip "Push-On" switch in probe saves batteries as power is applied only when needed.

Neu' DVM37

cuit loading on every measure-ment. That means 50°/0 higher accuracy than other DVMs.

DVM32 $198 3% DIGIT .5% DCV ACCURACY

PORTABLE DIGITAL MULTIMETER

Bench and field master for digital accuracy measurements anywhere. 0.5% DCV accur-acy, backed with 15 Megohm input imped-ance. Exclusive battery-saving Auto-Display turns the display on automatically when you make a measurement. 2000V input protect-ion on all functions and ranges—including Ohms.

DVM36 $158 3% DIGIT .5% DCV ACCURACY

POCKET PORTABLE DVM

Pocket portable lab accurate performance that fits every budget with highest perform-ance-to-price benefits of any meter. .5% DCV accuracy, backed with 15 Megohm input im-pedance for lowest circuit loading. Full pro-tection to 1000 V on all functions and ranges—including ohms. Drop-proof case. Battery-saving "Push On" button in probe.

DVM35 $134 3 DIGIT 1% DCV ACCURACY

POCKET PORTABLE DVM

Fast, direct reading digital accuracy for the man on the go. Same features as DVM36, except 3-digit, 1% DCV accuracy, backed by 15 Megohm input impedance that is ten times more accurate than analog meters.

DVM32 DVM36

r1 CD1 =t In stock at your favorite local Sencore Full Line Distributor. DIGITAL MULTIMETER SPECIALISTS 3200 Sencore Dr., Sioux Falls, SD 57107 (605) 339-0100

...for more details circle 127 on Reader Service Card

DECEMBER 1977. ELECTRONIC TECHNICIAN/DEALER / 13

SERVICE SEMINAR

The material used in this section is selected from information supplied through the cooperation of the respective manufacturers or their agencies.

ADMIRAL

Color TV Chassis K10 & K19—One or two thin, dark, vertical interference bars from left to center of picture These bars, which are more prevalent on the low VHF channels, may only be noticeable on weak signals or when using a built-in antenna. The position of the bars changes when the horizontal dynamic controls on the convergence board are adjusted. This is not the same as 'snivets' which are caused by the horizontal output tube during UHF op-eration. The problem can be corrected by adding a 680pf 500V capacitor across each of the clamp diodes on the con-vergence assembly, as shown in drawings below. The top diagram is for the K10 chassis, and the bottom diagram for the K19 chassis. Keep the leads short.

fling 7 •01•471 7' IN V W c Iff I wog. t int agl int(

Color TV Chassis M10—Service Hint for Replacing Transistor 0101 When replacing the forward pass transistor Q101 the tran-sistor socket may slip out of its retainer while inserting the new transistor. Improper installation could be the result with failure, then, of Q101, blown fuses, etc. To avoid this problem, insert a blunt rod or tool through the lower of the two holes in the bottom left rear of the chassis shown below, and to the left of the power supply panel. Pressure can then be applied to hold the socket in its retainer while removing and inserting the new transistor.

GTE SYLVANIA

Color TV Chassis E06/08/20/21 —Snowy UHF picture The cause is probably the RF AGC Delay (R276) set too high. Do not replace the UHF tuner. Instead, check the delay control.

BAN Chassis B-10-7—Horizontal oscillator will not start except when set has been in 'instant on' mode. Then it is off frequency. The fault is capacitor C400 which is shorted. Replace.

B/W Television (console)—Correction of VHF dial slippage Properly calibrate VHF dial, and then remove complete dial and hub assembly from tuner shaft. Install soft wire staple through the plastic dial and hub as shown in dia-

14 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

THE ANTENNA ORGANIZER THAT DOES MORE THAN DISPLAY ANTENNAS!

COMPREHENSIVE ASSORTMENT OF ANTENNA--TOP, CENTER 81 BASE LOADED MODELS--ALL INDIVIDUALLY SKIN PACKED FOR PROMINENT DISPLAY. SINGLE ANTENNAS SINGLE ANTENNA KITS CO-PHASED ANTENNA SYSTEMS MOUNTS & CABLES

UNIQUE "SWING-ASIDE - FLOOR MERCHANDISER LETS YOU GET MAXIMUM RETURN FROM MINI— MUM FLOOR SPACE. REQUIRES ONLY 5' x 2' AREA. LOOK WHAT YOU GET:

ELECTRONICS GC ELECTRONICS DIVISION OF HYDROMETALS INC

ROCKFORD ILLINOIS US A 61101 Ali

PROGRAM NO. 49-855

• 20 different antennas, antenna kits and co-phase systems-40 total products.

• Revolutionary "Swing-Aside" self-service floor merchandiser places entire selection at customer's finger tips.

• Colorful, descriptive header, complete with illustrations and catalog numbers, informs customer of the exact antenna or kit he desires.

• Versatility of selection allows 65 differ-ent antenna and mount combinations.

CONTACT YOUR GC

DISTRIBUTOR TODAY'

DECEMBER 1977, ELECTRONIC TECHNICIAN/DEALER / 15

NosimmommemommEmsom mEsi misimismim II I

I WHEN IT COMES TO 1 i s • i • • • • e • • • • • I I

• i j±neida's s SELECTION • • ..... IS ENDLESS! II

14

Oneida knows how important it is to have the right parts (sockets) at the right time. That's why your Oneida distributor can probably supply you with the

111 right socket for just about any job. 7-pin, 9-pin, 12-pin, circular, exact replacement, etc. Oneida has 'em by the hundreds.

111 IMMEDIATE DELIVERY FROM YOUR • ONEIDA DISTRIBUTOR

U

Viteida ONEIDA ELECTRONIC MFG,INC.

P.O. Box 678,8 aid wi n Street Ex L,Meadvil le,Pa.16335

Phone (814)336-2125

...for more details circle 123 on Reader Service Card

gram. Use a low wattage soldering iron to heat staple as you push it through hub and dial. Then bend staple over on the backside.

SOFT WIRE STABLE

STAPLE SHOWN THRU HUB & DIAL ASSY.

WIRE STAPLE PUSHED THRU FROM FRONT

AND BENT OVER.

GENERAL ELECTRIC

Color TV Chassis CD—Poor horizontal sync or no horizontal sync This refers to sets serial coded 5T3T and later sets with stick HV rectifier. The cause is a decrease in value or an open with the 39K, 112 watt resistor, R251. The solution is to replace R251 with a 39K, 1 watt 10e% carbon resistor.

Color TV Chassis MC & MB-75--When the grass is not green. To solve t his 'blue grass' problem, first, set up the tleshtone properly in both the auto and manual positions with the tint control. Then turn the core of L642 on the chroma

Use this versatile frequency counter when accuracy

counts. 11.1110 /CY c ouwir wn wo 7•••4

OVER II CI II 1-1 LI LI LI ./_s Lt

WD-752A $200.00

See it at your VIZ distributor

, VIZ 6644A

Exceptional accuracy and sensible features make our new wide-range frequency counter the ideal choice for checking out audio, video, CB, ham radio and other communications equipment. • Wide range -10Hz to 60MHz

• Precise 10.000MHz crystal-controlled time base for ±0.1ppm stability

• 1KHz audible tone for SSB carrier frequency measurement

• Selectable input sensitivity (for noise rejection) -10 or 100mV

• 6-digit bright LED readout

• Indicators for signal, overflow, and range

• Small and compact: ac operated

\l a Test Instruments Group

of VIZ Mfg. Co. 335 E. Price St., Philadelphia, Pa. 19144

...for more details circle 128 on Reader Service Card

16 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

module clockwise one full turn. This reduces the demodula-tion angle by about 25 degrees. Next, check the tint control in the manual position to make sure that the fleshtone range is still wide enough. Then widen fleshtone range, if necessary, by turning L642 counterclockwise until the de-sired results are attained. This adjustment is only possible on EP93X41 modules. It is fixed on EP93X89 modules.

MAGNAVOX

Radio Chassis R344—C202 capacitor failure A few R344 stereo console chassis were produced with a jumper at C202 installed. This jumper is intended for use only on the R342 and R343 chassis. When it has been installed wrongly in the R344, it can create distortion at high volume levels, and can eventually damage C202. If the jumper is found in an R344 chassis being serviced, remove the jumper.

Color TV Chassis T995—Replacing the teed-thru capacitance assembly In late production of the T995 chassis, three feed-thru ca-pacitors and two ferrite beads have been added to the hori-zontal output stage. The capacitors are soldered to a mount-ing bracket which is attached to the heat sink alongside the horizontal output transistor, Ql, as shown in the diagram. The connecting leads to the base and collector pass through the opening in the ferrite beads. If replacement of one of the feed-thru capacitors is neces-sary, you can save time by replacing the entire feed-thru assembly, which consists of the bracket and capacitors sol-dered in place. The ferrite beads are not provided because the originals can be re-used. Part number is 171441-1.

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DECEMBER 1977, ELECTRONIC TECHNICIAN DEALER 17

The author servicing an ECG amplifier module.

Tapping the medical electronics market

By Joseph J. Carr. C.E.T.•

II (Editor's Note: The sale of medi-cal industrial electronic equipment to medical institutions within the United States now constitutes a market that surpasses $660 mil-lion annually. It is expected that medical instrumentation sales will increase at a rate of 15 to 20 per cent through 1980. All of this equip-ment needs regular service and calibration. As part of ETID's goal of keeping the consumer electronics service industry aware of expand-ing opportunities, we present this general overview of the medical electronics service business and how to break into it). Biomedical equipment servic-

ing is one of the service industry's growth areas and potentially quite profitable for both service com-panies and individual technicians. Considering that some 1,300 manufacturers offer about 10,000 different models, the medical equipment industry obviously is healthy enough to structure a career around, or a business from. I know from experience that the

(*Mr. Carr is Senior Bioelectronics technician at the George Washington

University Medical Center, Washington, D.C.)

person who is really qualified to service a solid-state color televi-sion receiver is knowledgeable enough in basic electronics to learn medical equipment servic-ing. There's little that is exotic, but some specialized knowledge is required. So how do you get this knowl-

edge? The best is from a formal program at a college, university, or technical institute. A good background in electronics courses, plus a few courses in biomedical instrumentation or something similar would be in order. A number of community colleges now offer such programs and their popularity is growing everyday. And don't forget to check your

local library or scientific bookstore for such books as the one I have written, "Servicing Medical and Bioelectronic Equipment" (TAB Books No. 930). Medical equip-ment manufacturers themselves provide well written and complete service and training manuals on their own products.

WORKING IN THE HOSPITAL ENVIRONMENT

The hospital is a sensitive area,

18 / ELECTRONIC TECHNICIAN DEALER. DECEMBER 1977

A renal dialysis machine.

so things that might be margi-nally acceptable in other jobs or shops will be unacceptable in the hospital. When you enter a pa-tient's room to repair a cardiac monitor, for example, you are ex-pected to get in and out as quickly as possible. There's no room for the chit-chat that might be tolerated on a television service call. Extremely high standards of

craftsmanship are enforced in the hospital environment. Hospitals will give job preference to techni-cians who are certified by one of the existing certification groups (see accompanying list elsewhere in this article). Sloppiness in this business can be fatal. I recall the case where a defibrillator failed to operate when the doctors tried to resuscitate a heart attack victim. Subsequent examination revealed a classic case of bad craftsman-ship. A technician had soldered a tubular electrolytic across the open section of a multiple-section electrolytic capacitor in the power circuit. The bad section of the elec-trolytic eventually shorted to ground (as they often do) and this rendered the machine inoperable. e will never know if this killed

t e patient, but the technician ho takes such shortcuts has no siness in medical electronics. A point to remember if you con-

t mplate getting into medical e ectronics is that you won't be s rvicing electronics alone. Many ry important devices are actu-ly electro-mechanical in nature. Included in this list would be the

✓ nal dialysis "kidney machine."

It contains electrical as well as mechanical components and no small amount of plumbing. Other electro-mechanical devices you'll run up against are the intra-aortic balloon pump, heart lung ma-chines, autotransfusion pumps, respirators, suction pumps and a host of other devices.

KNOW YOUR MARKET

If you are a shop owner con-templating a medical service business, an investigation of your potential market will give you a good idea of your chances. In the larger cities there will probably be others doing the same type of work. However, smaller towns often offer the best opportunities. A reader in a small western

town wrote to me about a proposal he received from the local hospital administrator. The hospital wanted local service for their coronary care unit patient moni-toring system. The nearest factory service was out of San Francisco, some 600 miles away. Each service call, one every three weeks, cost not less than 8 to 10 hours in time (at $35 an hour). Add air fare for the technician and air freight for his equipment and parts, and the hospital ended up typically paying $500 per call—or about $9,000 a year. To check out your service shop's

potential in this area, first deter-mine who does the buying. Hospi-tal departments are economic ac-tivities not unlike businesses, and you may be able to sell your ser-vices to specific departments if not the whole institution. Service purchase decisions may

be made by any of the following people, either singly or in concert with each other: administrator, assistant administrator, purchas-ing director, director of materials management, medical doctors, de-partment heads, director of nurs-ing, head nurses in intensive care units, operating rooms, emer-gency rooms or dialysis units, and lastly the director of plant opera-tions. More recently, you may have to "sell" the clinical en-gineer, senior biomedical equip-ment technician (BMET), or a technical administrator.

WHAT SERVICES SHOULD YOU OFFER?

The two areas where many hos-

pitals seem to be potential cus-tomers are in repair and a regular preventive maintenance program. The repair function must be clearly defined so you will have to decide on what you can do. You should remember, too, it is virtu-ally mandatory you offer 24-hour service seven days a week. In fact this may help you get an account if the competition in your area does not provide such service, or fails to deliver as promised. In some cases, hospitals use outside vendors only after hours so that they do not have to pay a salary differential to the in-house technician. This then could be your foot in the door. If there are only a few hospitals

in your locale, and you want their general electronic repair business, it will be wise to assemble a list, by manufacturer and model number, of their intensive care, coronary care, operating room and emer-gency room monitoring equip-ment, all of the electrosurgery equipment in the OR, and all of their ECG (electro cardiogram) machines. Contact each manufac-turer to inquire about doing their service formally. If new installa-tions are contemplated inquire about becoming a warranty sta-tion. In any event, try obtaining all service manuals and other per-tinent literature, plus a list of rec-ommended spare parts. Generally the service technician at the plant is the best source of information. Preventive maintenance has

become a major consideration in hospitals because of the require-ments of the JCAH (Joint Com-mission on Accreditation of Hospi-tals) and insurance carriers. Also, it's necessary as a legal safeguard in medical malpractice suits. This job may be performed in-

house or by an outside contractor on a fee-for-service basis. The job may range from checking a piece of equipment to a complete me-chanical rebuilding. But, beware of contracts that leave you open to liability for the cost of some repair parts, as they can be quite costly.

BASIC TEST EQUIPMENT

Although some specialized equipment is necessary in medical electronic service, most of the test instruments required will be of the same sort as needed in any elec-tronic servicer operation. Oscilloscope: It should have a

DECEMBER 1977, ELECTRONIC TECHNICIAN/DEALER / 19

bandwidth of not less than 5-MHz (15-MHz is necessary if a lot of di-gital circuits are serviced). It should be dual trace and have a triggered sweep circuit. DMM: Capable of setting a po-

tential to 0-volts + 10-millivolts. This means at least 31/2-digits of resolution, which is no longer either uncommon or expensive. Electrosurgery apparatus are

high powered R.F. generators cap-able of delivering upwards of one ampere of R.F. current to a 500-Ohm (non-inductive) dummy load. Therefore you will need a tester that provides a means for observ-ing the waveform (safely!) on an oscilloscope. This capability is necessary for servicing some solid-state electrosurgery equip-ment. Another required instrument is

the electrical safety analyzer. Safety considerations in medical environments are far more critical than in other places, so a constant surveillance program must be fol-lowed. An addition to this is an electronic a.c. leakage current tester for more portable operation. The ECG waveform simulator,

affectionately dubbed a "chicken heart", is used to provide a reason-able waveform to ECG preamplifi-ers when troubleshooting or test-ing. Also required will be a defibril-

lator analyzer, and be sure to specify a model that has an oscil-loscope output jack. These devices are little more than a 50-Ohm dummy load, driving an integrat-ing voltmeter calibrated in watt-seconds. A leading supplier of specialized

test equipment for the BMET is Med-Search Systems, Inc.; 5480 Wisconsin Avenue; Chevy Chase, MD 20015. They are in a position to make up a starting package of instruments from several manu-facturers.

CERTIFYING ORGANIZATIONS There are two non-governmen-

tal organizations offering certifi-cation for medical electronics technicians—in addition to the Veteran's Administration which has its own certification proce-dure. Certified Electronic Technician

A bedside patient monitor system (courtesy of Electronics for Medicine).

(CET) program of ISCET (1715 Expo Lane; Indianapolis, IN. 46224). This organization offers a medical electronics option. Association for the Advance-

ment of Medical Instrumentation (AAMI-1901 Fort Myer Drive; Suite 602; Arlington, VA 22209). The AAMI also certifies clinical engineers, who are often responsi-ble for directing the efforts of BMET's in addition to performing the functions of consultant on medical equipment purchases, de-sign of new devices and facilties planning.

JOB ROLES IN MEDICAL ELECTRONICS The Biomedical Equipment

Technician (BMET) fills the most common job roles in medical elec-tronics regardless of whether he works for a vendor, manufacturer, or is employed in-house by a hospi-tal. His duties will be to trou-bleshoot, repair, calibrate, inspect and manage the maintenance of medical equipment as well as to instruct other hospital personnel on the proper operation of the equipment. Below are listed the most com-

mon functions of the BMET.

The Factory BMET: Usually works out of a local field office with

company car and modest expense account. Will service his compa-ny's line of equipment and make new installations. Generally they report incomes of $10,000 to $22,000.

In-House BMET: Salary gener-ally ranges from $10,000 to $16,000 a year. Works regular hours at the same location every day. He may be employed by the maintenance or "plant operations" section, one of the hospital's clini-cal departments, or a separate de-partment of biomedical or clinical engineering.

Independent Vendors: They come in two varieties, national corpora-tions and local service companies. The locals tend to be operated in much the same manner as con-sumer electronics and two-way radio shops. Pay is usually com-petitive but advancement may be limited due to smallness.

National Corporations, such as Honeywell, Inc., and The Stan-wick Corporation, provide main-tenance services. Pay and incen-tives are about the same as for manufacturer's technicians, but these technicians will service a much broader range of equipment than the factory servicer. •

20 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

Here Today, Gone Tomorrow.

At General Electric we're treating every TV parts order like a rush order. Here's how it's paying off: Over 99% of the General Electric TV replacement parts ordered this year were in stock in our national computer-linked parts dis-tribution system. And on the average better than 90% were ready for immediate shipment from the Regional Replacement Parts Centers. This is why most parts are now

shipped the same day an order's re-ceived or by the close of business the following day. But ordering parts from us is

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parts and one isn't immediately avail-able, we don't leave you hanging. Instead, we ship what's in stock and in-clude the expected shipping date for what isn't. How did General Electric's parts dis-

tribution come so far so fast? One factor was the enlargement of stocks at many

GE Parts Centers. But the deciding factor was our deter-mination to build a streamlined, efficient s3.stem that simplified the parts orcermg process for both of us. Now comes the easiest part of all. Clippiig out and

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Fig. 1—A section of the schematic for Admiral chassis 25M55M showing the source of +145 and +250 B + voltage supplies.

Admiral color television for 1978 Eight models in Admiral's 1978 color TV line feature

the new 25M55M chassis which is basically an M45

chassis with modifications. We take a look at the

changes.

II A total of thirteen new models make up the 1978 color TV line for Admiral. Five of the thirteen use last year's 9M50 chassis with elec-tronic tuning, and the remaining eight models feature the new 25M55M. chassis. All models use the negative matrix 90 degree delta CRT. The new 25M55M chassis is basically an M45 chassis which has been modified for full N-S and E-W pincushioning as well as to drive the larger 23-inch and 25-inch delta CRTs. Now let's take a look at circuitry which is new with the 25M55M chassis.

POWER SUPPLIES

The 25M55M is a line-connected chassis (Fig. 1) that gets its B+

from two basic rectifier supplies. One is a +145 volt source pri-marily used for horizontal and vertical sweep output. This supply is then decoupled to produce +130 volts for the audio output. The oth-er rectifier supply is a +250 volt source for the RGB output ampli-fiers. The +250 volt source is re-quired in the case of delta CRTs because a 140-150 volt bias is needed between cathodes and grids for gun cut-off. Actually, 170 to 180 volts of instantaneous signal/DC is used for gun cut-off because the control grids are al-ready operating at about 30 volts above ground. An isolation transformer must

be used during servicing as one side of the AC line is 'hot'. It's this

hot side that provides the AC source for the half wave diode, D900, used in the +145 supply, and diodes D130 and D131, as a half wave doubler to produce the +250 volt supply. The hot side of the AC line is also applied across PTC R900 and the degaussing coil, L102. The low voltage supply (+24

and +12 volts) that operates the front end, the tuners, the low level signal and low level sweep circuits comes through Module M600 but is derived from the positive flyback pulse (Fig. 2) that appears across the horizontal output trans-former, T101, secondary winding between pins 7 and 10. This is a pulse-derived supply even though it is often called 'scan-derived'. It is actually produced by the 40KHz flyback pulse oscillation. The +250 volt supply which, as

has been noted, is required by the delta CRT for gun cut-off, is pro-duced by the doubler circuit (Fig. 1) that includes diodes D130 and D131. This doubler circuit works in the following manner: Diode D130 starts to conduct to ground through capacitor C130 and resis-tors R130 and R133 during that half of the AC cycle when the 'hot'

22 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

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If your son is good at fixing up his stereo or if he knows his way around the wiring in your appliances, he may be eligible for about $17,000 worth of advanced technical training in electronics. And it won't cost you a cent.

For more information, tell him to talk to his local Navy Recruiter. Or mail the coupon below. For the fastest reply, call toll-free, 800-841-8000 anytime, day or night. The Navy.

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NAME (Please Print)

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DECEMBER 1977. ELECTRONIC TECHNICIAN/DEALER / 23

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side is negative with respect to chassis ground. This action charges capacitor C130 to near line voltage peak. Then, when the hot side of AC becomes positive with respect to ground during the other half cycle of AC, diode D131 starts to conduct with a path from ground through filter capacitors C133 and C134, and then through D131, R130 and C130 to the posi-

tive AC source. The two voltages produced combine to produce al-most twice as high a charge across filter capacitors C133 and C134 as could be obtained from a simple half wave rectifier.

THE SIGNAL SYSTEM

The signal circuits—front end AGC loop, Y video and chroma— are almost the same as in the pre-

vious M45 chassis except for some minor modifications. The changes, mainly, have been made to accom-modate the new delta CRT. For example, separate drive controls are used in the emitters of the green, blue and red amplifiers, as shown in Fig. 3. And separate G2 screen controls are included for each gun. The G2 supply voltage is produced by a separate diode in

24 / ELECTRONIC TECHNICIAN/DEALER, DECEMBER 1977

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the H.V tripler, M100, (Fig. 2) and is obtained from the flyback pulse input return winding at pin 12 of the horizontal output transformer. The +250 voltage supply de-

scribed earlier is used as the R,G, and B collector source for cut-off of the CRT guns. A +145 volt supply was used for this purpose in the earlier M45 chassis.

PRE-SET CONTROLS

When the Admiral color control (ColorMaster) system is in opera-tion, pre-set adjustments for tint. color and brightness are substi-tuted for manual customer con-trols. The connections from the control assembly to the chassis are made through jack J110 and plug P110.

Brightness

Whether pre-set or manual, the brightness control varies the posi-tive DC voltage at pin 1 of P110 (Fig. 4). This voltage is applied to the anode of the Video-Emitter/ Follower, Q700. Because of DC coupling through the remainder of the "Y" channel, the DC bias volt-age is altered at the CRT cathodes which in turn changes the average

color gain increases as the voltage is decreased toward zero volts.

CRT gun conduction and, there-fore, brightness.

Color

The color gain control (Fig. 4) varies the DC voltage on pin 4 of P110. The voltage is then applied to pin 6 of the Chroma Amp and Demodulator IC400 which, in turn, varies the gain of the 2nd chroma amplifier in the IC. The

Tint

Depending on the ColorMaster setting by the customer, either the manual or pre-set tint control arm (Fig. 4) is connected to pin 6 of P110. This connection shifts the 3.58MHz oscillator output phase, which in turn, changes the de-

DECEMBER 1977, ELECTRONIC TECHNICIAN/DEALER / 25

modulation angle of the demod-ulators in IC400. The source DV voltage for the tint control poten-tiometers appears on pin 5 of P110. The altered tint voltage from the arm of either manual or pre-set tint control is applied to pin 1 of Subcarrier Regenerator IC401.

CONTRAST CONTROL In Admiral's 25M55M chassis,

the contrast control is not pre-set. It is a manual control in series with a video level pre-set, which is a service adjustment. The video

level control selects the proper peak-to-peak composite video for the "Y" channel input. Admiral's service literature for the 25M55M chassis points out that this video level control is necessary because there is no signal loop gain level adjustment for the front-end AGC gain loop, and thus the composite video can vary widely from set to set. The contrast control center arm

(Fig. 4) is connected to pin 3 of P110 and then through a 10 mfd coupling capacitor (C701) to the

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Satisfaction Guaranteed You risk nothing. These shirts and the lettering are guaranteed to please you in every way. Money back or new shirts if not satisfied.

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ORDER HERE! COMPLETE SATISFACTION GUARANTEED! ELIN UNIFORM MFG. CO.

Dept. 940 Rochester, Indiana 46975 Here s my check for $39.90. Ship 6 guaranteed shirts postpaid. Sizes, colors, lettering & lettering colors are checked at right.

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